OBJECTIVE: We present the first report of agenesis of the middle nasal turbinate. METHOD: We present a case report and briefly discuss the world literature. RESULTS: A 57-year-old man presenting with sinonasal symptoms was evaluated clinically and radiologically. Agenesis of the patient's left middle turbinate was detected. Coronal computed tomography images showed a septal spur replacing the absent left middle turbinate. CONCLUSION: The lateral nasal wall has complex anatomy, and several anatomical variations have been reported. The most common anatomical variation of the middle nasal turbinate is concha bullosa. Unilateral agenesis of the middle nasal turbinate has not previously been reported; the presented patient represents the first reported case.